The piping systems that deliver potable water and fire fighting capabilities in tall buildings have unique requirements. They must be able to withstand not only high pressures, but seismic and wind forces that can cause the building to sway. Speed and ease of assembly are also important factors during the construction phase as builders grapple with tighter deadlines and a more fluid, less skilled workforce.
Ball valves made of stainless steel.
So as buildings grow ever taller, engineers are turning to stainless steel piping systems to meet these needs. Three of the newest and tallest buildings in the world, the Taipei Financial Centre in Taiwan and the Petronas Twin Towers in Kuala Lumpur, are prime examples of this shift away from more traditional copper and plastic pipes to high-pressure stainless steel piping systems in certain circumstances.
The Taipei Financial Centre, a 101-storey, 509-metre high building completed in 2004 uses the Victaulic grooved stainless steel system for fire protection and plumbing and Victaulic valves and stainless steel pipes up to 318 millimetres for hot and cold water supply.
The Victaulic grooved system provides the flexibility to withstand any seismic activity, up to the strongest earthquake in a 2,500 year cycle. The system, designed especially for standard or light-wall stainless steel, is also more cost-effective than traditional methods of welding, flanging or threading because it can be installed quickly using unskilled labour and is easy to access for cleaning and maintenance.
In the Taipei Financial Centre, the pipes for domestic water supply are made of JIS 3459 Schedule 10 stainless steel for corrosion resistance. They have a wall thickness of 9.52 millimetres to accommodate pipes up to 318 millimetres and pressures of 300 psi (2065 kPa). Both hot and cold water can run through the system because the couplings are flexible enough to handle thermal expansion and contractions and the gaskets are rated from -34 to 100 degrees Celsius.
In addition, the stainless steel valves are designed to handle one-and-a-half times the system pressure and have a “dead-end” shut-off service to isolate equipment for maintenance. An absorber in the system prevents water hammer.
Type 304 stainless steel pipes and Victaulic couplings are also used in the Petronas towers, the tallest buildings in the world, to accommodate high pressures and vibration.
For smaller diameter piping systems that don’t require ready access, Victaulic’s Pressfit system (also marketed as the Mapress system) provides economy, reliability and fast installation. The system uses 316 or 304 stainless steel pipe with fittings that can be permanently attached using a handheld electric tool, eliminating the risk of fire and the need for welded or threaded joints.
This type of system is currently being installed in Brisbane’s tallest residential tower, the Aurora, scheduled for completion in January 2006. According to Blucher Australia, which supplied the 108mm piping, the 316 stainless steel pipe has a wall thickness of two millimetres for pressures of approximately 355 psi (2490 Kpa). The pumps are electronically controlled by the water reservoir level at the top of the building for a slow-start up that prevents water hammer.
“No other pipe systems can withstand continuous mains pressure water flows, extreme changes in water temperatures and the clean-in-place routines as well as stainless steel,” said Mogens Jensen, managing director of Blucher Australia is a recent article for ferret.com.au, an on-line information source for suppliers in Australia.